Note 3 - Inventories - Components of Inventory (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Mar. 31, 2019
Raw materials	$ 422	$ 495
Work in process	2,427	4,032
Finished goods	8,199	6,587
Supplies	158	160
Inventories, net	$ 11,206	$ 11,274

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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